Nvidia’s valuation fell to $4.3 trillion after a 25% drawdown from its Oct 6 peak of $5.8 trillion wiped out $1.5 trillion in market value and handed the title of the world’s most valuable company back to Apple. Nvidia shares dropped 4.2% on Monday following news of a board investigation involving CEO Jensen Huang and amid investor concerns over whether AI infrastructure spending will generate adequate returns, leaving the stock down 4% year to date and 10% over the past 12 months.

The slide deepened a 30% decline over 34 days from Nvidia’s intraday high, erasing $1.81 trillion at its trough as shares broke below $180 ahead of its Nov 17 earnings report. The pullback pushed Nvidia’s daily relative strength index to its most oversold reading in 7.5 years and cost the chipmaker the top weighting in both the S&P 500 and Nasdaq 100 indexes to Apple.

Nvidia had briefly retaken the top valuation spot at roughly $5.02 trillion against Apple’s $4.85 trillion on Nov 3, when Apple fell about 4% after its first earnings report under CEO John Ternus. Although Apple posted a 12% rise in September quarter revenue to $114.48B and guided December quarter growth of 7% to 10%, CFO Kevan Parekh projected holiday gross margins would fall to 45% to 46% from 47.9% due to Siri AI ramp expenses and “unprecedented” memory pricing.